The Immune System: Imaged at Last

HHMI Bulletin | February 2006

If the thought of invasive medical procedures makes you queasy, HHMI investigator Owen N. Witte points out that “there’s a noninvasive trend in medical diagnosis—to measure things inside the body without having to stick tubes in a patient or do an operation.” Witte, a researcher at the University of California, Los Angeles, has recently furthered this trend, leading a team from three medical institutions to develop a noninvasive technique based on positron emission tomography (PET). The scientists captured three-dimensional views of one body component never before seen from the outside—the immune system.
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The Fate of Brain Cells

HHMI Bulletin | December 2005

A fountain of youth springs from within the brain of every mammal, report HHMI investigator Alexandra L. Joyner and her former postdoctoral associate Sohyun Ahn in the October 6, 2005, issue of Nature. No, the two researchers haven’t unlocked the secret to immortality. But their discovery of a method to visualize an elusive population of stem cells that has the potential to regenerate nerves and other brain cells may explain how certain regions of the brain rejuvenate themselves. Moreover, the findings may allow researchers to tap the revitalizing powers of stem cells for repairing injured and diseased brain tissue.
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Protein Disposal: Gumming Up the Works

HHMI Bulletin | September 2005

For a cell, destroying proteins is as essential as building them. The job of mincing proteins is performed by enzymatic machines called proteasomes. “Proteasomes affect almost all biological processes in the cell,” Verma says. By their deliberate destruction of regulatory proteins, they orchestrate activities from cell division to cell death. read in full issue (pdf)

DNA Microarray Virtual Lab

Genetic Science Learning Center | February 2005

DNA microarray analysis is one of the fastest-growing new technologies in the field of genetic research. Scientists are using DNA microarrays to investigate everything from cancer to pest control. Now you can do your own DNA microarray experiment! Here you will use a DNA microarray to investigate the differences between a healthy cell and a cancer cell. virtual lab